This product works well and is simple to use. It kept water cold all day long, which was not cold without it. It stayed in backpack where it was supposed to. I used it every day for a week, and no problem.

Yep! It'll work on any Deuter pack with a space for a hydration bladder. One of the photos of the Kid Comfort II shows the regular Streamer in use, but this Thermo Streamer is basically the same size plus a bit of insulation around it.